Appearance->"Vertical"->{h,w} will display the controls in a grid with the specified number of columns and rows, vertically filling each column in turn. Appearance->"Horizontal"->{h,w} horizontally fills the rows instead.

If one of h or w is Automatic, it is taken to be the smallest number so that all the controls will fit in the resulting grid. If both h and w are Automatic, they are calculated so the grid has roughly the same number of rows as columns.

The settings for BaseStyle are appended to the default style typically given by the style in the current stylesheet.